This invention relates to an improved molecule separator and relates also to an improved method of making a molecule separator.
Molecule separators are typically used for separating a carrier gas from a specimen in gaseous form to be analysed by, for example, a mass spectrometer. The molecule separator is connected between the output of a gas chromatograph, for example, and the input of the ion source of the mass spectrometer. The separator may have one or more separating stages and in one commonly known construction, the separator consists of an evacuation chamber connected to a vacuum pump, a jet input nozzle arranged to be connected to the gas chromatograph and through which molecules in gas phase are supplied, and a coaxial output nozzle arranged to be connected to the analysing instrument.
The jets of the molecule separator are normally spaced apart a distance approximately 0.1 mm and they also generally have a diameter of about 0.1 mm, although it is not uncommon for the diameter of one jet -- that is the output jet -- to be larger than the input jet. Heretofor, it has been difficult to ensure completely accurate alignment of the jets in a molecule separator which is essential for the separator to function correctly.